Brief introduction to the function of the cooling device for the packaging belt production of the packaging steel belt manufacturer

Brief introduction to the function of the cooling device for the packaging belt production of the packaging steel belt manufacturer
　　 In order to obtain dimensionally stable products, it is very important to control a lower material temperature from the end of the homogenization section of the main machine to the head part. The lower polymer temperature is easy to maintain the shape of the extrudate and facilitate cooling.
　　 The product is cooled after being extruded by the die, generally water cooling is used. The strip extruded from the die enters the cooling water tank and is cooled by 10-20 cm long air. Under the action of high temperature such as homogenization section and die head, the material presents a viscous flow state. The temperature is submerged in the air, and enters the cooling water tank with the traction speed. The cooling water temperature is generally required to be about 40-60 ℃. Fast, the less the molecular weight loss, the faster the molding, but too low temperature will cause the material to crystallize suddenly, and the molding will be too rapid, the product will appear ripples and flow. The water temperature is too high, so that the material cannot be shaped for a long time after extruding the die, and the molecular weight is lost. The product cannot be completely cooled and shaped under the action of the drafting speed. Therefore, it is necessary to have good cooling conditions. Maintain a stable cooling rate and level. If the cooling is not good, the material will be affected in the secondary drafting, resulting in uneven drafting and even breakage. So there must be good and stable cooling conditions.
　　 The temperature of the cooling water tank is affected by heat, so the water surface must have a stable and stable cooling temperature, generally the upper part has a high temperature and the lower part has a low temperature. Therefore, after the product exits the mold, it is fully cooled at the bottom of the water tank and then sent to the pre-drafting device.